Yarrowia lipolytica is one of the most studied “non-conventional” oleaginous yeasts. It is able to produce a number of valuable proteins and metabolites such as lipases and other hydrolytic enzymes, single cell oils (SCOs), single cell proteins (SCPs), carboxylic acids, erythritol and ?-decalactone (Nicaud, 2012). Scientific research is focusing on Y. lipolytica due to its ability to grow on different carbon sources, both hydrophobic and hydrophilic, and to its high tolerance to broad pH ranges and salt concentrations (Miller and Halper, 2019). Lipases (EC 220.127.116.11) are a class of hydrolases which naturally catalyze the hydrolysis of triglycerides to glycerol and free fatty acids at the oil–water interface in the presence of emulsions. Furthermore, lipases are very important for the synthesis of esters through esterification and transesterification reactions in anhydrous conditions, with high enantioselectivity. For their ability to catalyze specific biotransformations in different reaction media, lipases have been employed in several industrial sectors, from the pharmaceutical to food and chemical industries (Treichel et al., 2010). Y. lipolytica use as a sustainable platform for lipase production has been investigate using waste cooking oils (WCOs). The term WCO refers to oils and fats from food processing and storage at a commercial, industrial or household level. In Europe, WCOs annual production accounts for approximately 4 million tons/y (EBIA, 2021). If not collected and properly disposed of, WCOs can form the so-called “fatbergs” that can damage and clog the sewage system and pollute water and soil (Foo et al., 2014).
In this work, the capabilities of Y. lipolytica to grow on high concentrations of different hydrophobic carbon sources, such as Olive Oil and WCOs, among others, were investigated to evaluate their potential as inducers for lipase production.